[Maukey]

I have 2 new contenders, the Master & Dynamic MW75 and the Bowers & Wilkins PX7 S2. Could either or both enter the top 5? More to come

 

[Maukey]

I have added the Master & Dynamic MW75 AMG Edition and the Bowers & Wilkins PX7 S2

 

[Maukey]

Up next, the Momentum 4

 

[starfly]

@Maukey

Have you ever used the Sony XM4? Between the PX7 S2, H95, MW75, and 5909, how do they rank in terms of ANC?

Also would you mind posting ear cup dimensions? In particular of the inside of the earcup, length x width x depth in mm. Doesn't have to be perfectly accurate, just to get a general idea.

I ask because while the Sony XM4 has excellent ANC, they're not that comfortable for extended wear, and I have big ears. I'm a regular flyer and the drivers of the XM4 sit right on my ear, which makes the cartilage start to hurt after a while. They're not deep at all. Looking for a replacement (XM5 is even worse in that regard).

So am really looking for a pair of cans that are very comfortable for wearing for many hours, have great ANC (though I know nothing will beat Sony) and have good codec support (preferably LDAC).

Edit: I just saw you also have the Momentum 4 now. Would you mind measuring those as well? And ranking ANC?

 

[Maukey]

@Maukey

Have you ever used the Sony XM4? Between the PX7 S2, H95, MW75, and 5909, how do they rank in terms of ANC?

Also would you mind posting ear cup dimensions? In particular of the inside of the earcup, length x width x depth in mm. Doesn't have to be perfectly accurate, just to get a general idea.

I ask because while the Sony XM4 has excellent ANC, they're not that comfortable for extended wear, and I have big ears. I'm a regular flyer and the drivers of the XM4 sit right on my ear, which makes the cartilage start to hurt after a while. They're not deep at all. Looking for a replacement (XM5 is even worse in that regard).

So am really looking for a pair of cans that are very comfortable for wearing for many hours, have great ANC (though I know nothing will beat Sony) and have good codec support (preferably LDAC).

Edit: I just saw you also have the Momentum 4 now. Would you mind measuring those as well? And ranking ANC?

Yes I've used the XM4 and XM5, both are better than every headphone on this list when it comes to strictly ANC. I I will say, I've only spent one day with Momentum 4, but their ANC has definitely improved over the Momentum 3. Much, much better. I would rank ANC as follows from best to worst....XM4/XM5 -> AirPods Max -> Bose 700/QC Series -> Momentum 4/M&D MW75/ML 5909/PX7 S2 (Need to compare more, they're all close) -> B&O H95 (No longer own so going off of memory)

I'm currently on my way out of town with my family so I won't be able to measure right now, but I will say if roomy ear cups is what you need for comfort, hands down the ML 5909 and the Momentum 4 are what you want. The original PX7 has roomy ear cups as well, but higher clamping force. Of course the Bose QuietComfort series has roomy ear cups and are super light. So yeah, for comfort and roomy cups, I'd say the ML5909 if your budget allows, the Momentum 4, which I'm loving by the way, or the Bose QuietComfort 35 II or 45.

In summary, if ANC is priority, get the Bose. Fairly neutral sound, and arguably the most comfortable, all day wearing headphones you can buy. If you're ok with still great ANC, but want better sound (better, more natural tonality, with a better soundstage and more detail than the Bose), the Momentum 4 are tough to beat. The ML 5909 offer the best sound with top tier comfort, but they're really expensive. I also don't prefer really big headphones for travel, so I personally wouldn't use them as travel headphones. That's just me though.

 

[raymanh]

Great thread this!

I'd love to hear your opinions on something more on the budget side, particularly the new Anker Soundcore Space Q45. The previous models (Q30 and Q35) were praised for their value and I'd be curious to see how the new models stacks up.

 

[starfly]

Yes I've used the XM4 and XM5, both are better than every headphone on this list when it comes to strictly ANC. I I will say, I've only spent one day with Momentum 4, but their ANC has definitely improved over the Momentum 3. Much, much better. I would rank ANC as follows from best to worst....XM4/XM5 -> AirPods Max -> Bose 700/QC Series -> Momentum 4/M&D MW75/ML 5909/PX7 S2 (Need to compare more, they're all close) -> B&O H95 (No longer own so going off of memory)

I'm currently on my way out of town with my family so I won't be able to measure right now, but I will say if roomy ear cups is what you need for comfort, hands down the ML 5909 and the Momentum 4 are what you want. The original PX7 has roomy ear cups as well, but higher clamping force. Of course the Bose QuietComfort series has roomy ear cups and are super light. So yeah, for comfort and roomy cups, I'd say the ML5909 if your budget allows, the Momentum 4, which I'm loving by the way, or the Bose QuietComfort 35 II or 45.

In summary, if ANC is priority, get the Bose. Fairly neutral sound, and arguably the most comfortable, all day wearing headphones you can buy. If you're ok with still great ANC, but want better sound (better, more natural tonality, with a better soundstage and more detail than the Bose), the Momentum 4 are tough to beat. The ML 5909 offer the best sound with top tier comfort, but they're really expensive. I also don't prefer really big headphones for travel, so I personally wouldn't use them as travel headphones. That's just me though.

Thanks, man. If at some point you do get around to taking measurements, I'd appreciate it.

And good to know about the Momentum 4. I'll need to give those a shot. What I do like about the 5909 is that they support both AptX and LDAC. I use a Samsung phone, so the only way to get a high bit rate is with LDAC, as Samsung in their infinite wisdom only supports basic AptX which isn't much better than SBC. They're very expensive though, so I'd need to think hard about those, but supreme comfort is definitely a draw.

 

[Ikhemsek]

Thanks for making this comparison! Fairly new to the whole hobby and looking to upgrade from my current budget wireless ANC setup, and the Px7 S2 and MW75 were top of the list under consideration. This is literally the only resource I’ve found in my research thus far that has compared the two directly, since both are significantly more niche than Sony or Bose and most literature out there seems restricted to individual reviews for each rather than head-to-head comparisons. Looking forward to seeing a more granular ranking in ANC between the Px7 S2 and MW75 and especially the new Momentum 4’s as well since there’s not a huge amount of reviews out yet given its recency. The 5909’s look sublime but I’ve had a bit of difficulty locating places with them in stock and even fewer that ship to here- would have jumped on them in a heartbeat elsewise.

Great thread this!

I'd love to hear your opinions on something more on the budget side, particularly the new Anker Soundcore Space Q45. The previous models (Q30 and Q35) were praised for their value and I'd be curious to see how the new models stacks up.

Also quite curious to hear more on this, the Q35 has served me exceptionally well in terms of ANC and comfort for the price, I wonder if the Q45 has made any strides in ANC performance relative to Sony or if the sound profile has changed substantially.

 

[starfly]

Alright, I got to compare the ML 5909, B&W PX7 S2, Technics EAH-A800 and Sony XM4 side by side. I won't go into too much detail on the sound differences, but will focus more on the ANC and comfort aspects. Here are my impressions:

Sound:
1 PX7 S2 - honestly stands out the most. It's just fun to listen to and seems versatile with many different kinds of music. My favorite of the bunch
2. 5909 - is a close second. Sound is Harman Curve, and honestly it puts the high-mids a bit too much forward to my liking. Otherwise pretty detailed, and crisp highs, excellent sub-bass extension (especially with the enhanced profile, which only boosts the sub-bass but leaves mid-bass alone - doesn't bleed at all into the mids) - versatile sound signature. Also supports both AptX and LDAC!
3. Momentum 4 - initial listening impressions put these here in the middle of the pack. Pretty fun sound signature, but still fairly balanced.
4. EAH-A800 - comes fourth without ANC. With ANC it comes way at the bottom, as the ANC gives the sound a weird hollow underwater reverb-ish quality. Without ANC it has a fun sound signature
5. XM4 - comes last in this comparison. But perhaps it's because I've had these for a year and I'm used to the sound signature - they just don't stand out to me, kinda blah.

Sorry if my sound impressions aren't more descriptive

ANC (tested by just turning on a white noise machine at roughly 65-70dB and seeing how well it mutes that noise, and not playing any music on the headphones):
1. XM4 - this one has the best, as is well known
2. Momentum 4 - this has surprisingly great ANC. It really blocked out the white noise effectively, and didn't introduce any weirdness to the music.
3. PX7 S2 - actually quite good. Not as good as the XM4, but better than I expected.
4. EAH-A800 - ANC cancels noise pretty well, but it has the downside of giving everything this hollow underwater quality. And any movement gets picked up by the ANC system and somehow makes it into the cans.
5. 5909 - last, not that impressed with the ANC. A lot of the white noise still came through, I was expecting better based on the reviews I read. Not that big of a difference between ANC-off (passive noise isolation is pretty good at least) and ANC-high. Granted, this wasn't an elaborate test, and only at a single white noise frequency range - maybe other frequency ranges would be cancelled better.

Comfort (my ears are about 67mm long, so above average ear size, and my head is narrow and tall. Earcup measurements made with digital caliper):
1a. PX7 S2 (56x36mm earcup) - tie with the 5909. These have the smallest earcups in this group, but they're surprisingly comfortable. Might be partly due to the angled drivers, which means the rear part of the ear has more space and it can sort of nuzzle underneath the pad without touching the driver. I just have to position the earcups as far back and as high as possible, so that the bottom part of the cup rests on my earlobes a bit and the top part of my ear doesn't get squished. Longest I've worn them was about 2 hours so far and my ears were only minimally sore. No clear feeling of my ears touching the inside of the cups or the drivers. Headband is pretty comfortable, clamping force is above average but not uncomfortable.
1b. 5909 (63x39mm earcup) - these have the largest earcups in this comparison and thus have the most room for my ears. I can still feel my left ear in particular touching the rear wall of the earcup, which is a little bit annoying. But the pads are plush, clamping force is pleasant (less than the PX7 S2), headband is pretty comfortable. I could probably wear these for a few hours and only the back of my left ear would be a bit irritated. But deep enough that I don't feel the drivers resting on my ears. No angled drivers otherwise. Comfortwise giving the edge to the PX7 S2.
2. EAH-A800 (60x41mm earcup) - pretty comfortable, but I can feel the back of my ear touching the earpad (it's always my left ear - my right ear doesn't seem to care), more noticeably than on the 5909. Earcups feel roomy otherwise, and are deep enough to not have the drivers rest on your ear, but my ears still touch the fabric that covers the drivers. No angled drivers (I think having angled drivers is one of the keys to improved comfort).
3. Momentum 4 (58x36mm earcup) - the earpads are soft and plush, and the drivers are angled. A good starting point. But they might be too soft, as I can already feel my ears touching the fabric on the drivers and the inside of the earcups. That will become annoying quick after an hour or so.
4. XM4 (62x40mm earcup) - not that comfortable after an hour - the stock pads compress too much to the point that the drivers rest directly on my ears, making my ear cartilage hurt a lot after a while. This is really what started my search for another pair of wireless ANC headphones.

Overall:
Honestly I'm pleasantly surprised by the PX7 S2. They're fun headphones to listen to, and more comfortable than I would have expected given their relatively small size. The only downside I experienced here is that the B&W Music app, on Android, is really buggy and usually won't connect with the headphones (eventhough the headphone is connected to the phone just fine and streaming music over Bluetooth). Not a huge dealbreaker as the stock sound signature is great and I don't need to mess with Bass/Treble sliders, and everything else can be controlled from the headphone.

5909 are really nice headphones, but I'm not sure of the value proposition, given that they're $1K. Don't feel like they're worth $1K. At $600-$700 they'd be much better value. And also, the ANC was not at all impressive. But comfort is good and they have extensive codec support (my current Samsung phone only supports LDAC, and basic AptX, but not AptX Adaptive). Still considering these. App experience is fine, though there aren't many settings you can change.

Momentum 4 have unexpectedly good ANC in my test. The best in the bunch here after the XM4. But the small and shallow earpads are a dealbreaker. I've only tested them for a short while and will give it a more extended listening session.

EAH-A800 is most likely going back, with the weird SQ with ANC on (without ANC they sound fine). I do like that these have LDAC support, and the interaction with the companion app worked well.

XM4 - well I already own these so no decision needs to be made on these. Not planning on selling them or giving them away. They have by far the best ANC of the bunch. Comfort can be improved with after market pads (I've tested 2 so far, both by Dekoni - their Choice Pleather pads which are really deep greatly improve comfort, but at a huge ANC expense. Their Earpadz Platinum brand slightly improves comfort with a minimal ANC penalty - both obviously affect SQ, but that can potentially be EQ'ed to compensate).

Overall I'm still on the fence on which one to keep. I wish the PX7 S2 had even bigger earpads, as then they'd be perfect - they still require a lot of repositioning to find the perfect spot - and even then I do notice them after an hour or so (that darn left ear of mine!!). Maybe the upcoming PX8 will - but I doubt it based on some drawings I pulled from the FCC website - looks to be the same earcup size. But it seems like angled drivers are one of the key to improved comfort, and these are pretty comfortable and cozy for what they are.
The 5909 I wish it had better ANC and was cheaper. It's a tough value proposition at $1K. They could be more comfortable, even though they have the biggest pads. Angled drivers could have really improved the comfort.
The Momentum 4 I wish had bigger earpads, and I would have considered them. But alas that will be dealbreaker.
EAH-A800 - Technics could've had a winner here if they hadn't botched the SQ with ANC on - I guess there's a reason the Head-Fi thread here only has 2 pages worth of posts.

At this point I'm actually leaning towards keeping none of these. I'm realizing more and more that comfort is the most important factor to me in a wireless ANC headphone, as I use them for travel to block out noise on airplanes and other noise environments. For serious music listening I have better wired headphones than any of these wireless ones, and I general prefer to just listen over speakers for serious listening anyway (will beat any headphone any day, in my opinion).

I have another set of earpads for the XM4 on the way that are according to the reviews very comfortable with a minimal impact to ANC. And they're only $30. If that doesn't solve the comfort issue, I might have to try the Bose QC45. I did briefly own the NC700 once and wore them on an intercontinental flight and remembered I could wear them the whole time without any real discomfort (if anything just the headband pressing down on my head). I gave those away to my brother right after, and the QC45 is supposed to be even more comfortable. If I went for those, AAC bluetooth will have to suffice I guess, if it otherwise means supreme comfort for many hours.

I think all these manufacturers spend too little time thinking about comfort and what can really bother the end user. In my opinion, a real over-ear size headphone would have earcups with inner dimensions of at least 70x50mm, and the drivers would be at least 30mm away. That would make headphones a bit bigger (but not that much bigger. As it is, most of these headphones are more semi over-ear, or an on-ear/over-ear hybrid.

 

[starfly]

Added Momentum 4 impressions above and changed my overall conclusion.

 

[matteventu]

Alright, I got to compare the ML 5909, B&W PX7 S2, Technics EAH-A800 and Sony XM4 side by side. I won't go into too much detail on the sound differences, but will focus more on the ANC and comfort aspects. Here are my impressions:

Sound:
1 PX7 S2 - honestly stands out the most. It's just fun to listen to and seems versatile with many different kinds of music. My favorite of the bunch
2. 5909 - is a close second. Sound is Harman Curve, and honestly it puts the high-mids a bit too much forward to my liking. Otherwise pretty detailed, and crisp highs, excellent sub-bass extension (especially with the enhanced profile, which only boosts the sub-bass but leaves mid-bass alone - doesn't bleed at all into the mids) - versatile sound signature. Also supports both AptX and LDAC!
3. Momentum 4 - initial listening impressions put these here in the middle of the pack. Pretty fun sound signature, but still fairly balanced.
4. EAH-A800 - comes fourth without ANC. With ANC it comes way at the bottom, as the ANC gives the sound a weird hollow underwater reverb-ish quality. Without ANC it has a fun sound signature
5. XM4 - comes last in this comparison. But perhaps it's because I've had these for a year and I'm used to the sound signature - they just don't stand out to me, kinda blah.

Sorry if my sound impressions aren't more descriptive

ANC (tested by just turning on a white noise machine at roughly 65-70dB and seeing how well it mutes that noise, and not playing any music on the headphones):
1. XM4 - this one has the best, as is well known
2. Momentum 4 - this has surprisingly great ANC. It really blocked out the white noise effectively, and didn't introduce any weirdness to the music.
3. PX7 S2 - actually quite good. Not as good as the XM4, but better than I expected.
4. EAH-A800 - ANC cancels noise pretty well, but it has the downside of giving everything this hollow underwater quality. And any movement gets picked up by the ANC system and somehow makes it into the cans.
5. 5909 - last, not that impressed with the ANC. A lot of the white noise still came through, I was expecting better based on the reviews I read. Not that big of a difference between ANC-off (passive noise isolation is pretty good at least) and ANC-high. Granted, this wasn't an elaborate test, and only at a single white noise frequency range - maybe other frequency ranges would be cancelled better.

Comfort (my ears are about 67mm long, so above average ear size, and my head is narrow and tall. Earcup measurements made with digital caliper):
1a. PX7 S2 (56x36mm earcup) - tie with the 5909. These have the smallest earcups in this group, but they're surprisingly comfortable. Might be partly due to the angled drivers, which means the rear part of the ear has more space and it can sort of nuzzle underneath the pad without touching the driver. I just have to position the earcups as far back and as high as possible, so that the bottom part of the cup rests on my earlobes a bit and the top part of my ear doesn't get squished. Longest I've worn them was about 2 hours so far and my ears were only minimally sore. No clear feeling of my ears touching the inside of the cups or the drivers. Headband is pretty comfortable, clamping force is above average but not uncomfortable.
1b. 5909 (63x39mm earcup) - these have the largest earcups in this comparison and thus have the most room for my ears. I can still feel my left ear in particular touching the rear wall of the earcup, which is a little bit annoying. But the pads are plush, clamping force is pleasant (less than the PX7 S2), headband is pretty comfortable. I could probably wear these for a few hours and only the back of my left ear would be a bit irritated. But deep enough that I don't feel the drivers resting on my ears. No angled drivers otherwise. Comfortwise giving the edge to the PX7 S2.
2. EAH-A800 (60x41mm earcup) - pretty comfortable, but I can feel the back of my ear touching the earpad (it's always my left ear - my right ear doesn't seem to care), more noticeably than on the 5909. Earcups feel roomy otherwise, and are deep enough to not have the drivers rest on your ear, but my ears still touch the fabric that covers the drivers. No angled drivers (I think having angled drivers is one of the keys to improved comfort).
3. Momentum 4 (58x36mm earcup) - the earpads are soft and plush, and the drivers are angled. A good starting point. But they might be too soft, as I can already feel my ears touching the fabric on the drivers and the inside of the earcups. That will become annoying quick after an hour or so.
4. XM4 (62x40mm earcup) - not that comfortable after an hour - the stock pads compress too much to the point that the drivers rest directly on my ears, making my ear cartilage hurt a lot after a while. This is really what started my search for another pair of wireless ANC headphones.

Overall:
Honestly I'm pleasantly surprised by the PX7 S2. They're fun headphones to listen to, and more comfortable than I would have expected given their relatively small size. The only downside I experienced here is that the B&W Music app, on Android, is really buggy and usually won't connect with the headphones (eventhough the headphone is connected to the phone just fine and streaming music over Bluetooth). Not a huge dealbreaker as the stock sound signature is great and I don't need to mess with Bass/Treble sliders, and everything else can be controlled from the headphone.

5909 are really nice headphones, but I'm not sure of the value proposition, given that they're $1K. Don't feel like they're worth $1K. At $600-$700 they'd be much better value. And also, the ANC was not at all impressive. But comfort is good and they have extensive codec support (my current Samsung phone only supports LDAC, and basic AptX, but not AptX Adaptive). Still considering these. App experience is fine, though there aren't many settings you can change.

Momentum 4 have unexpectedly good ANC in my test. The best in the bunch here after the XM4. But the small and shallow earpads are a dealbreaker. I've only tested them for a short while and will give it a more extended listening session.

EAH-A800 is most likely going back, with the weird SQ with ANC on (without ANC they sound fine). I do like that these have LDAC support, and the interaction with the companion app worked well.

XM4 - well I already own these so no decision needs to be made on these. Not planning on selling them or giving them away. They have by far the best ANC of the bunch. Comfort can be improved with after market pads (I've tested 2 so far, both by Dekoni - their Choice Pleather pads which are really deep greatly improve comfort, but at a huge ANC expense. Their Earpadz Platinum brand slightly improves comfort with a minimal ANC penalty - both obviously affect SQ, but that can potentially be EQ'ed to compensate).

Overall I'm still on the fence on which one to keep. I wish the PX7 S2 had even bigger earpads, as then they'd be perfect - they still require a lot of repositioning to find the perfect spot - and even then I do notice them after an hour or so (that darn left ear of mine!!). Maybe the upcoming PX8 will - but I doubt it based on some drawings I pulled from the FCC website - looks to be the same earcup size. But it seems like angled drivers are one of the key to improved comfort, and these are pretty comfortable and cozy for what they are.
The 5909 I wish it had better ANC and was cheaper. It's a tough value proposition at $1K. They could be more comfortable, even though they have the biggest pads. Angled drivers could have really improved the comfort.
The Momentum 4 I wish had bigger earpads, and I would have considered them. But alas that will be dealbreaker.
EAH-A800 - Technics could've had a winner here if they hadn't botched the SQ with ANC on - I guess there's a reason the Head-Fi thread here only has 2 pages worth of posts.

At this point I'm actually leaning towards keeping none of these. I'm realizing more and more that comfort is the most important factor to me in a wireless ANC headphone, as I use them for travel to block out noise on airplanes and other noise environments. For serious music listening I have better wired headphones than any of these wireless ones, and I general prefer to just listen over speakers for serious listening anyway (will beat any headphone any day, in my opinion).

I have another set of earpads for the XM4 on the way that are according to the reviews very comfortable with a minimal impact to ANC. And they're only $30. If that doesn't solve the comfort issue, I might have to try the Bose QC45. I did briefly own the NC700 once and wore them on an intercontinental flight and remembered I could wear them the whole time without any real discomfort (if anything just the headband pressing down on my head). I gave those away to my brother right after, and the QC45 is supposed to be even more comfortable. If I went for those, AAC bluetooth will have to suffice I guess, if it otherwise means supreme comfort for many hours.

I think all these manufacturers spend too little time thinking about comfort and what can really bother the end user. In my opinion, a real over-ear size headphone would have earcups with inner dimensions of at least 70x50mm, and the drivers would be at least 30mm away. That would make headphones a bit bigger (but not that much bigger. As it is, most of these headphones are more semi over-ear, or an on-ear/over-ear hybrid.

Have you also tried the B&O H95 by any chance?

 

[starfly]

Have you also tried the B&O H95 by any chance?

No. By all accounts it doesn't have great ANC, so not worth it at that cost IMO. So I didn't even consider trying, and it doesn't look like it has big earpads anyway. OP tried it though.

 

[starfly]

@Maukey are you able to post ear cup size measurements of the H95? Now I've gotten curious. And how would you rank ANC of the H95 against the PX7 S2?

 

[Maukey]

@Maukey are you able to post ear cup size measurements of the H95? Now I've gotten curious. And how would you rank ANC of the H95 against the PX7 S2?

Sorry, I no longer own the H95. I think the PX7 S2 may be a slight step up off of memory and comparing it directly with the 5909

 

[nunomeneses]

Alright, I got to compare the ML 5909, B&W PX7 S2, Technics EAH-A800 and Sony XM4 side by side. I won't go into too much detail on the sound differences, but will focus more on the ANC and comfort aspects. Here are my impressions:

Sound:
1 PX7 S2 - honestly stands out the most. It's just fun to listen to and seems versatile with many different kinds of music. My favorite of the bunch
2. 5909 - is a close second. Sound is Harman Curve, and honestly it puts the high-mids a bit too much forward to my liking. Otherwise pretty detailed, and crisp highs, excellent sub-bass extension (especially with the enhanced profile, which only boosts the sub-bass but leaves mid-bass alone - doesn't bleed at all into the mids) - versatile sound signature. Also supports both AptX and LDAC!
3. Momentum 4 - initial listening impressions put these here in the middle of the pack. Pretty fun sound signature, but still fairly balanced.
4. EAH-A800 - comes fourth without ANC. With ANC it comes way at the bottom, as the ANC gives the sound a weird hollow underwater reverb-ish quality. Without ANC it has a fun sound signature
5. XM4 - comes last in this comparison. But perhaps it's because I've had these for a year and I'm used to the sound signature - they just don't stand out to me, kinda blah.

Sorry if my sound impressions aren't more descriptive

ANC (tested by just turning on a white noise machine at roughly 65-70dB and seeing how well it mutes that noise, and not playing any music on the headphones):
1. XM4 - this one has the best, as is well known
2. Momentum 4 - this has surprisingly great ANC. It really blocked out the white noise effectively, and didn't introduce any weirdness to the music.
3. PX7 S2 - actually quite good. Not as good as the XM4, but better than I expected.
4. EAH-A800 - ANC cancels noise pretty well, but it has the downside of giving everything this hollow underwater quality. And any movement gets picked up by the ANC system and somehow makes it into the cans.
5. 5909 - last, not that impressed with the ANC. A lot of the white noise still came through, I was expecting better based on the reviews I read. Not that big of a difference between ANC-off (passive noise isolation is pretty good at least) and ANC-high. Granted, this wasn't an elaborate test, and only at a single white noise frequency range - maybe other frequency ranges would be cancelled better.

Comfort (my ears are about 67mm long, so above average ear size, and my head is narrow and tall. Earcup measurements made with digital caliper):
1a. PX7 S2 (56x36mm earcup) - tie with the 5909. These have the smallest earcups in this group, but they're surprisingly comfortable. Might be partly due to the angled drivers, which means the rear part of the ear has more space and it can sort of nuzzle underneath the pad without touching the driver. I just have to position the earcups as far back and as high as possible, so that the bottom part of the cup rests on my earlobes a bit and the top part of my ear doesn't get squished. Longest I've worn them was about 2 hours so far and my ears were only minimally sore. No clear feeling of my ears touching the inside of the cups or the drivers. Headband is pretty comfortable, clamping force is above average but not uncomfortable.
1b. 5909 (63x39mm earcup) - these have the largest earcups in this comparison and thus have the most room for my ears. I can still feel my left ear in particular touching the rear wall of the earcup, which is a little bit annoying. But the pads are plush, clamping force is pleasant (less than the PX7 S2), headband is pretty comfortable. I could probably wear these for a few hours and only the back of my left ear would be a bit irritated. But deep enough that I don't feel the drivers resting on my ears. No angled drivers otherwise. Comfortwise giving the edge to the PX7 S2.
2. EAH-A800 (60x41mm earcup) - pretty comfortable, but I can feel the back of my ear touching the earpad (it's always my left ear - my right ear doesn't seem to care), more noticeably than on the 5909. Earcups feel roomy otherwise, and are deep enough to not have the drivers rest on your ear, but my ears still touch the fabric that covers the drivers. No angled drivers (I think having angled drivers is one of the keys to improved comfort).
3. Momentum 4 (58x36mm earcup) - the earpads are soft and plush, and the drivers are angled. A good starting point. But they might be too soft, as I can already feel my ears touching the fabric on the drivers and the inside of the earcups. That will become annoying quick after an hour or so.
4. XM4 (62x40mm earcup) - not that comfortable after an hour - the stock pads compress too much to the point that the drivers rest directly on my ears, making my ear cartilage hurt a lot after a while. This is really what started my search for another pair of wireless ANC headphones.

Overall:
Honestly I'm pleasantly surprised by the PX7 S2. They're fun headphones to listen to, and more comfortable than I would have expected given their relatively small size. The only downside I experienced here is that the B&W Music app, on Android, is really buggy and usually won't connect with the headphones (eventhough the headphone is connected to the phone just fine and streaming music over Bluetooth). Not a huge dealbreaker as the stock sound signature is great and I don't need to mess with Bass/Treble sliders, and everything else can be controlled from the headphone.

5909 are really nice headphones, but I'm not sure of the value proposition, given that they're $1K. Don't feel like they're worth $1K. At $600-$700 they'd be much better value. And also, the ANC was not at all impressive. But comfort is good and they have extensive codec support (my current Samsung phone only supports LDAC, and basic AptX, but not AptX Adaptive). Still considering these. App experience is fine, though there aren't many settings you can change.

Momentum 4 have unexpectedly good ANC in my test. The best in the bunch here after the XM4. But the small and shallow earpads are a dealbreaker. I've only tested them for a short while and will give it a more extended listening session.

EAH-A800 is most likely going back, with the weird SQ with ANC on (without ANC they sound fine). I do like that these have LDAC support, and the interaction with the companion app worked well.

XM4 - well I already own these so no decision needs to be made on these. Not planning on selling them or giving them away. They have by far the best ANC of the bunch. Comfort can be improved with after market pads (I've tested 2 so far, both by Dekoni - their Choice Pleather pads which are really deep greatly improve comfort, but at a huge ANC expense. Their Earpadz Platinum brand slightly improves comfort with a minimal ANC penalty - both obviously affect SQ, but that can potentially be EQ'ed to compensate).

Overall I'm still on the fence on which one to keep. I wish the PX7 S2 had even bigger earpads, as then they'd be perfect - they still require a lot of repositioning to find the perfect spot - and even then I do notice them after an hour or so (that darn left ear of mine!!). Maybe the upcoming PX8 will - but I doubt it based on some drawings I pulled from the FCC website - looks to be the same earcup size. But it seems like angled drivers are one of the key to improved comfort, and these are pretty comfortable and cozy for what they are.
The 5909 I wish it had better ANC and was cheaper. It's a tough value proposition at $1K. They could be more comfortable, even though they have the biggest pads. Angled drivers could have really improved the comfort.
The Momentum 4 I wish had bigger earpads, and I would have considered them. But alas that will be dealbreaker.
EAH-A800 - Technics could've had a winner here if they hadn't botched the SQ with ANC on - I guess there's a reason the Head-Fi thread here only has 2 pages worth of posts.

At this point I'm actually leaning towards keeping none of these. I'm realizing more and more that comfort is the most important factor to me in a wireless ANC headphone, as I use them for travel to block out noise on airplanes and other noise environments. For serious music listening I have better wired headphones than any of these wireless ones, and I general prefer to just listen over speakers for serious listening anyway (will beat any headphone any day, in my opinion).

I have another set of earpads for the XM4 on the way that are according to the reviews very comfortable with a minimal impact to ANC. And they're only $30. If that doesn't solve the comfort issue, I might have to try the Bose QC45. I did briefly own the NC700 once and wore them on an intercontinental flight and remembered I could wear them the whole time without any real discomfort (if anything just the headband pressing down on my head). I gave those away to my brother right after, and the QC45 is supposed to be even more comfortable. If I went for those, AAC bluetooth will have to suffice I guess, if it otherwise means supreme comfort for many hours.

I think all these manufacturers spend too little time thinking about comfort and what can really bother the end user. In my opinion, a real over-ear size headphone would have earcups with inner dimensions of at least 70x50mm, and the drivers would be at least 30mm away. That would make headphones a bit bigger (but not that much bigger. As it is, most of these headphones are more semi over-ear, or an on-ear/over-ear hybrid.

I had px7 carbon and shure and I went comparing both with AirPods Max. Loved the sound signature of px7 but lack of detail in highs made me return them. Comfort and anc on shure made me return them. Airpods Max are fine on all fronts but sound is not that energy for me. But it has great anc and good amount of detail. Does px7 s2 has that level of detail?